Jukka Leinonen

Publications (4)15.17 Total impact

• Article: Gene expression profiling in the submandibular gland, stomach, and duodenum of CAVI-deficient mice.

  Pei-wen Pan, Katri Käyrä, Jukka Leinonen, Marja Nissinen, Seppo Parkkila, Hannu Rajaniemi
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  ABSTRACT: Carbonic anhydrase VI (CAVI) is the only secreted isozyme of the α-carbonic anhydrase family, which catalyzes the reversible reaction [Formula in text]. It appears that CAVI protects teeth and gastrointestinal mucosa by neutralizing excess acidity. However, the evidence for this physiological function is limited, and CAVI may have additional functions that have yet to be discovered. To explore the functions of CAVI more fully, we generated Car6 (-/-) mice and analyzed Car6 (-/-) mutant phenotypes. We also examined transcriptomic responses to CAVI deficiency in the submandibular gland, stomach, and duodenum of Car6 (-/-) mice. Car6 (-/-) mice were viable and fertile and had a normal life span. Histological analyses indicated a greater number of lymphoid follicles in the small intestinal Peyer's patches. A total of 94, 56, and 127 genes were up- or down-regulated in the submandibular gland, stomach, and duodenum of Car6 (-/-) mice, respectively. The functional clustering of differentially expressed genes revealed a number of altered biological processes. In the duodenum, the significantly affected biological pathways included the immune system process and retinol metabolic processes. The response to oxidative stress and brown fat cell differentiation changed remarkably in the submandibular gland. Notably, the submandibular gland, stomach, and duodenum shared one important transcriptional susceptibility pathway: catabolic process. Real-time PCR confirmed an altered expression in 14 of the 16 selected genes. The generation and of Car6 (-/-) mice and examination of the effects of CAVI deficiency on gene transcription have revealed several affected clusters of biological processes, which implicate CAVI in catabolic processes and the immune system response.
  Transgenic Research 06/2011; 20(3):675-98. · 2.75 Impact Factor
• Article: Erratum to: Gene expression profiling in the submandibular gland, stomach, and duodenum of CAVI-deficient mice.

  Pei-Wen Pan, Katri Käyrä, Jukka Leinonen, Marja Nissinen, Seppo Parkkila, Hannu Rajaniemi
  Transgenic Research 02/2011; · 2.75 Impact Factor
• Article: VAMP8/endobrevin as a general vesicular SNARE for regulated exocytosis of the exocrine system.

  Cheng-Chun Wang, Hong Shi, Ke Guo, Chee Peng Ng, Jie Li, Bin Qi Gan, Hwee Chien Liew, Jukka Leinonen, Hannu Rajaniemi, Zhi Hong Zhou, Qi Zeng, Wanjin Hong
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  ABSTRACT: The molecular mechanism governing the regulated secretion of most exocrine tissues remains elusive, although VAMP8/endobrevin has recently been shown to be the major vesicular SNARE (v-SNARE) of zymogen granules of pancreatic exocrine acinar cells. In this article, we have characterized the role of VAMP8 in the entire exocrine system. Immunohistochemical studies showed that VAMP8 is expressed in all examined exocrine tissues such as salivary glands, lacrimal (tear) glands, sweat glands, sebaceous glands, mammary glands, and the prostate. Severe anomalies were observed in the salivary and lacrimal glands of VAMP8-null mice. Mutant salivary glands accumulated amylase and carbonic anhydrase VI. Electron microscopy revealed an accumulation of secretory granules in the acinar cells of mutant parotid and lacrimal glands. Pilocarpine-stimulated secretion of saliva proteins was compromised in the absence of VAMP8. Protein aggregates were observed in mutant lacrimal glands. VAMP8 may interact with syntaxin 4 and SNAP-23. These results suggest that VAMP8 may act as a v-SNARE for regulated secretion of the entire exocrine system.
  Molecular Biology of the Cell 04/2007; 18(3):1056-63. · 4.94 Impact Factor
• Article: Salivary carbonic anhydrase isoenzyme VI

  Jyrki Kivelä, Seppo Parkkila, Anna-Kaisa Parkkila, Jukka Leinonen, Hannu Rajaniemi
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  ABSTRACT: The carbonic anhydrases (CAs) participate in the maintenance of pH homeostasis in various tissues and biological fluids of the human body by catalysing the reversible reaction CO2+ H2O ⇌ HCO3−+ H+ (Davenport & Fisher, 1938; Davenport, 1939; Maren, 1967). Carbonic anhydrase isoenzyme VI (CA VI) is the only secretory isoenzyme of the mammalian CA gene family. It is exclusively expressed in the serous acinar cells of the parotid and submandibular glands, from where it is secreted into the saliva. In this review, we will discuss recent advances in research focused on the physiological role of salivary CA VI in the oral cavity and upper alimentary canal.
  The Journal of Physiology 09/2004; 520(2):315 - 320. · 4.72 Impact Factor